PALO ALTO, CALIF. April 27, 2004 Varian Medical Systems, Inc. (NYSE:VAR) today announced it has received 510(k) clearance from the U.S. Food and Drug Administration (FDA) for a new single-channel device for delivering High-Dose Rate (HDR) brachytherapy. Varian’s MammoSource afterloader is a computer-controlled device that delivers a high-energy radioactive source through a single catheter, into the cavity left when a tumor has been surgically removed.It works with Varian’s BrachyVision™ software, a state-of-the-art image guided HDR brachytherapy treatment planning system.

“Varian’s new afterloader responds to the needs of cancer centers that are seeking a cost-effective solution for offering partial-breast irradiation following lumpectomy,” said William Hyatt, vice president and general manager of Varian’s BrachyTherapy business. “Our single channel system is specifically engineered for these single catheter treatments and is designed to reduce the capital cost barriers often faced by hospitals wishing to offer the new accelerated breast brachytherapy techniques. We are excited about this opportunity to help make these new treatment options available to more of our customers and their patients.”